Circuit controller



Mdy 21," 1929. w, c, STEVENS 1,713,931

0 IRCUI T CONTROLLER Filed April 29, 1927 2 Sheets-Sheet l lllllllllmlll IN VEN TOR.

A TTORNEY y 21, 1929- w. c. STEVENS CIRCUIT CONTROLLER Filed April 29 1927 2 Sheets$heet 2 INVENTOIF. ,C. Sm MW.

g I I ATTORNEY Patented May 21, 1929.

UNITED STATES- PATENT OFFICE.

WILLIAM C. STEVENS, OF MILWAUKEE, WISCONSIN, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO CUTLER-HAMMER INC., 01? MILWAUKEE, WISCONSIN, A CORPORA- TION OF DELAW'ARE.

CIRCUIT CONTROLLER.

Application filed April 29,

This invention relates to circuit controllers, and more particularly to protective devices therefor.v

The invention has among its objects to provide a circuit controller having improved protective means associated therewith for preventing return of the controller to off posit-ion upon the occurrence of abnormal conditions, until or unless such abnormal condi-.

1o tions have existed for a predetermined interval.

Another object is to provide a low voltage protective mechanism employing a low volt age release magnet, and means for temporarily holding the armature thereof in closed position under low voltage conditions, and for thereafter permitting unrestrained move ment thereof. 7

Another object is to provide simple, compact and reliable protective mechanism of the aforesaid character employing a sucker device for delaying return of the controller to ofi position under low voltage conditions.

Various other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate an embodiment ofthe invention which will now be described, it being understood that the invention is not limited to the particular type of controller shown, and that the embodiment illustrated is susceptible of modification without departing from the spirit and scope of the appended claims.

In the drawing,

.Figure 1 is a fragmentary front elevational view of an auto-transformer starter having a low voltage protective mechanism embodyin the invention associated therewith, certam parts of such mechanism being shown in section.

Fig. 2 is a fragmentary side elevational View of thestarter shown in Fig. 1, the casing of the starter and also portions of the protective mechanism being shown in section.

Fig. 3 is a sectional viewsimilar to that shown in Fig. 2 but illustrating certain parts of the protective mechanism in another portion.

Fig. 4-is a plan view of the low voltage protective mechanism, and 7 1 Fig. 5 is a view taken substantially on line 5-5 of Fig. 2, in the direction indicated by arrows.

The invention is shown'in connection with 1927. Serial No. 187,582.

an auto-transformer starter of the type including a movable contact element having extreme starting and running positions and an intermediate off position. Starters of this character are well known in the art and therefore only a fragmentary showing and a brief description thereof is necessary for understanding the invention.

The starter is shown as comprising a rotatable contact element 10 immersed in oil within a tank 11 suspended from an enclosing casing 12. Contact element 10 is provided with a rotatable operating shaft 13 supported at opposite ends by suitable bearings, one of which is indicated at 14 in Fig. 2. Shaft 13 has a plate 15 fixed thereto which is provided with cam surfaces 16 and 17 and as best shown in Fig. 5, the casing 12 carries a pivoted arm 18 having a roller 19 on the free end thereof which is biased towards said cam surfaces by a spring 20 connected to said arm and to the casing 12. The cam surfaceslG and 17 are so shaped that engagement of the roller 19 therewith serves to bias the contact element 10 towards an intermediate off position upon movement thereof in opposite directions out of such position. Contact element 10 cooperates with a plurality of stationary contacts, not shown, and upon a movement thereof in one direction out ofoif position the same establishes starting connections through the medium of auto-transformer windings, one of which is indicated by reference character 25 in Fig. 2, while movement thereof in anopposite direction out of off position establishes running connections. The contact element 10 is provided with an operating handle 21 which is fixed to an angular projection 22 on the plate 15, and said plate is also provided with an arm 23 having a projection 24 on the free end thereof to be engaged by a latch associated with a low voltage release magnet.

The low voltage release magnet includes a magnet winding 25 provided with a laminated U-shaped core member 26 and a laminated armature member 27. As best shown in Fig. 2, the core member 26 is fixed to casing 12 by bolts 26' and the winding 25 is mounted upon the upper leg thereof, while the armature member 27 is pivotally secured to the lower leg thereof. The armature 27 is provided'with a latch 28 immediately below the pivot thereof to cooperate with the projection l BI'SJtiIigfOIlditlOIlS armature 27 is held in. closed position by the winding 25 and as same to "c losedpos'ition; Under normal opshown in Fig. 2, the latch 28 then engages 'the'under side of projection .24to hold the contact element 10. in running position.

Under :low voltage conditions the winding releases. the armature 27 and contactele-r gages the roller 41 on arm 39 to connect the.

mentlOthen tends toatrip the latch 28 and return tooff'position. However, a timing mechanism which will now be describedris provided. to delay tripping ofthe latch 28 to thereby prevent-return of thecon-troller to ofi' position for a predetermined interval underlowror no voltage conditions.

The timlng mechanism includes a cup mem- 1 her 30 carried by a support 31 and a sucker element 32 arrangediwithin said cup member and :adaptedto be connected to the ar- 1 mature27. Support 31'comprises a hollow.

member havingqflanges 33"and 34.arrange'd at right jangles to each other, and said sup port is :fixed to the casing 12 by bolts] 35 pass ing through the flange 33 while the cup member 30 is fixed to the flange 34 by. screws 36'. Thecu-p' member 30 preferably carries sufiicient oil therein to cover the sucker element '32 andthe samehas a plurality ofpius fixed to the bottom wall thereof which project; upwardly ,into openings in the sucker elementzto guide thelatter. v 1 L Thesucherelement 32has a latch38 associated therewith which'is arrangedto co-' operate with an; arm. 39 associated withthc armature 27. Asbestshown 1n Figs. 2 and 4, thearm 39 is fixed to armature 27 immediately below the pivot thereof by bolts .40, and

the same projects ;-.outwardly through Yan: opening inf'ca'sin 12 into the support 31." Y The free end of arm 39 has a roller 41 mounted thereon to be engaged by the latch 38: and saidrlatch is pivot-ally mounted upon a pin 42 carried between projections on the upper ifaceof'th'e. sucker element 32; Latch: 38 iszbiased to move in a counterclockwise di.- rection .(Figs. 2 and 3) by a spring,43,-andv movement thereof beyond th eposition shown in 2 is limited by astop 44 thereon which engages the upper face of thesucker element 32. The latch 38 is provided with ashoulder 46' for engaging the roller'41, and the same is also provided with cam surfaces '47 and 48,

the former surface to cooperate with the roller 41 on arm39,'and the latter-t0 cooperate; with a roller-.49 carried by a pin 50 fixed to the support 31.

.As-before stated, upon movement of the auto-transformer-.starter into running position, the-proj.ection- 24 on arm 23 engages the underi's de of thearm-ature 27. to move the;

latter into closed position and if the armature is'held in this position by magnet 25'thelatch 28 engages the under side of the projection V 24-tohold the starter in running posltion.

sucker element 32 to the armature members27 as shown in'Fig. 2.

Under low voltage conditions the controller tends to trip the latch 28 and return toofiiposi tion, but with the parts positioned as shown.

in Fig. 2it is apparentthat the sucker. ele-..

ment 1 32 acts. through the medium of; the

latch 38 and arm 39 to hold latch 28 in its lock-1 ing position. However,. after-a given. interval the sucking effect of element. 32 isovercome and the latch :28-is thenpermitted itor trip whereupon the controllerreturns to off;

position. Upon tripping oflat-c'h'28, the arm 39, latch 38 and sucker element 32-1nove up:-

. wardly and when said sucker element :reaches the positionshown in Fig. 4 the roller. 49 cooperates with thecam surface '48 on. latch.

38 to move the latter out-of engagementiwithi the roller 41. The'sucker-element then drops. under the action of gravity to thenormalpof SltlOIl'ShOWn 1n Flg. 2.

In connection with the fore oingjit should a; be notedithat under low voltage: conditions the aforede'seribed timing mechanisminsures;

against movement ofthe armature. 27 and its f latch 28out-of locking position 150m prede 'j termined interval and then permits. substaII-Lv tially unrestrained trippingmovement'theree.

of. It shouldalsobe notedthat withtheaparts arranged as above described the suckerdevi'cei of the timing mechanism can :beiofjrelatively small size and also such timing mechanism can; be applied to existingitypes of starters without. material change in the; design thereof. r H f What I'claim. as new. and desire tosecure; by Letters Patent is: V

'1. The combination with Iacircuit controller, of .a tripping mechanism. therefor includ; ing alatch5 allow voltage magnet for holding. said latch in looking position'andasuckende.

vice including adhering parts. one of which is associated with said latch for delayingiripe ping thereof under.low'voltageconditions.

2. The combination with a circuit control: ler; of a tripping mechanism therefor-,includincluding astationaryelemen't and'an adhere ing movable element, and means for connect:

I ing a latch a low voltage magnet for'holdingf' L said latchin locking position, a sucker. device sucker element being operatively connected to said latch.

4. The combination a with an auto-transformer starter including a movable contact clement biased towards off position, of means for holding said element in an operative po sition, comprising alatch having a low voltage holding winding associated therewith, a sucker device including a stationary element and a sucker element adapted to adhere thereto, a second latch for connecting said sucker element to said former latch to delay tripping thereof under low voltage conditions, and

' means for tripping said second latch upon initial tripping movement of said former latch.

5. The combination with a motor starter including a part to be tripped under low voltage conditions, and means for delaying tripping of said part comprising a device including a stationary element and a movable sucker element adhering thereto and operatively connected to said part.

6. The combination with a motor starter having a low voltage release mechanism associated therewith, of an enclosing casing for said starter and a timing device mounted on the exterior of the enclosing casing of said starter and adapted to delay tripping of said low voltage release mechanism, said device includin g a stationary part and a movable sucker element adhering thereto and operatively connected to said mechanism.

7. The combination with a motor starter, of a tripping mechanism therefor, including a pivoted latch, an arm fixed to said latch, a timing device comprising a stationary cup member and a movable sucker element therein, and means for connecting said sucker element to said arm upon setting of said latch and for disconnecting the same therefrom upon tripping of said latch.

8. In a circuit controller, the combination with a low voltage release mechanism, of means for delaying operation of said mechanism for a predetermined interval under low voltage conditions and for thereafter permitting unrestrained operation thereof, said means comprising a sucker device having a movable element operatively connected to said mechanism.

9. In a circuit controller, the combination with a low voltage release mechanism, of means for delaying operation of said mechanism for a predetermined interval under low voltage conditions, and for thereafter permitting unrestrained operation thereof, said means comprising a sucker device having a movable element, a releasable connect-ion between said sucker element and said mechanism, and means for tripping said connection upon tripping of said latch.

In witness whereof, I have hereunto subscribed my name.

WILLIAM C. STEVENS. 

